Regulatory linkage between epibiotic organisms and their host zooplankton populations is one of the least understood topics in zooplankton biology, despite the likely importance of epibionts to pelagic communities. These laboratory studies with...

The image of a child standing at the side of a creek and skipping stones across it exemplifies how we tend to mentally separate aquatic habitats from dry land. But there is a constant exchange of materials from land to streams, and vice-versa....

We evaluate mobility predictors in wireless networks. Handoff prediction in wireless networks has long been considered as a mechanism to improve the quality of service provided to mobile wireless users. Most prior studies, however, were based on...

Many environmental toxicants found in pesticides, herbicides, and industrial solvents are believed to have deleterious effects on development by disrupting hormone-sensitive processes. Xenopus embryos were exposed to commonly encountered endocrine...

In this dissertation, I present an examination of the role of two biotic interactions in the population dynamics of Vibrio cholerae. Traits with a genetic basis such as size, physiological processes, stress tolerance, and even behavior, are key...

A nocturnal activity pattern is central to almost all hypotheses on the adaptive origins of primates but this view has been challenged recently on the basis of variation in the cone opsin genes of nocturnal primates. The diversity among primates in...

Mutualisms may facilitate coupled population expansion or decline if changes in either partner species lead to similar changes in the other species. However, few studies have measured how both species in a mutualism respond to changes in each...

Toxoplasma gondii is an obligate intracellular pathogen that is able to survive in a range of hosts due to its repertoire of secreted effector proteins. Utilizing the type I and type II Δku80 strains we engineered a collection of targeted knockout...

Understanding mercury (Hg) and lead (Pb) accumulation and retention in forest soils is needed to reduce their negative impacts on human and wildlife health. In addition, mercury and lead can be used to characterize the role of soil in terrestrial...

Identifying the determinants of reproductive success in small-scale societies is critical for understanding how natural selection has shaped human evolution and behavior. The available evidence suggests that status-accruing behaviors such as...

Arctic soils in the permafrost region store substantially more carbon than is contained in the atmosphere, and are undergoing rapid change associated with anthropogenic climate change. Soil decomposition is an important component of ecosystem...

Antibodies are known to be a primary correlate of protection in almost all current vaccines, and thus evaluating the antibody response is of critical importance in attempting to predict the efficacy of novel vaccine candidates. Historically...

This dissertation examines the behavioral and physiological adaptations employed by modern humans to subsist in tropical rainforests. I employ various theoretical and methodological approaches to test hypotheses using empirical data from African...

Steep terrain produces a topographic effect in digital satellite data that can make it difficult to distinguish changes in vegetation species or health from changes in illumination geometry. A multiple linear regression analysis of direct solar...

Populations are, by definition, a collection of individuals, so the mechanisms of population change often occur at the level of the individual. The goal of this research was to examine how variability in the behavior of individual females...

Understanding the processes that determine the abundance of migratory birds has been difficult because these species move between diverse locations on different continents. Furthermore, events during one stage of the annual cycle are likely to...

Within a species, the abundance of individuals varies in time and space. This dissertation research examines processes giving rise to patterns of spatial and temporal variation in the abundance of multiple species of forest-breeding migratory...

The main research objective of this thesis is to address distributed target tracking for mobile sensor networks. Based on real-life limitations, we are particularly interested in mobile sensors with Limited Sensing Range (LSR). There are three...

Identifying and understanding sources of individual variation in fecundity is of central importance to life history theory and population ecology. In this study, I first examined how factors on the breeding grounds in eastern Maryland affected the...

In this study, I examined the interactive effects of prey and physical habitat on foraging, habitat selection, growth, and survival of age-0 Atlantic salmon, Salmo salar. I combined field observations of salmon behavior, surveys of habitat and prey...

Iron minerals are ubiquitous in near surface environments and often readily sorb or coprecipitate with many trace metals. Transformations of iron phases are, therefore, integral to the fate of trace metals in most near surface aqueous regimes....

One of the principle aims of ecology is to understand variations in organism abundance over time. Some species and species assemblages exhibit exceptionally dynamic changes in abundance or biomass, while other species and species assemblages are...